Happy First Birthday, Yipes!

This update was written by Smithsonian Conservation Biology Institute ungulate keepers Tara Buk and Chris Mathews.

From the moment Hartmann’s mountain zebra Yipes was born July 2, 2020, his arrival brought our animal care team abundant joy. He playfully tossed blades of grass in the air like confetti. He rolled around in the mud until he was black, white and red. And, he leapt into the air when he stopped to smell a flower and a butterfly unexpectedly took flight. Amidst all of the challenges of the past year, Yipes was undoubtedly a bright spot, and we have enjoyed watching him grow.

Today, we celebrate our confident and independent zebra colt’s first birthday! Normally, we scatter Yipes’ diet around the pasture so he can forage for hay, grass, pellets, bamboo, autumn olive browse (leavy branches) and mulberry browse. In honor of his special day, however, we presented Yipes with a giant “cake” made of zebra-friendly foods! The base of the cake is made of hay, complete with grass “icing” and pellet “sprinkles.” We topped it off with a carrot “candle” and a slice of apple for the “flame.” He seemed very interested in the treat, and it wasn’t long before he was nibbling away!

Hartmann's mountain zebra Yipes stands atop a scale in the barn.
To monitor Yipes' weight, keeper Tara Buk trained him to step on a scale. He receives cinnamon biscuits and pellets as a reward for his participation.

Although Tara has many fond memories of working with Yipes, her favorite moment was when he voluntarily stepped onto a scale for the first time. Ever since Yipes was young, our ungulate care team has worked to acclimate him to the barn’s stalls, chutes and other equipment that helps us manage our herd. Even so, Hartmann’s mountain zebras tend to be very wary of new objects and unfamiliar spaces.

One way we desensitize the zebras to their environment is through positive reinforcement training. We teach them husbandry behaviors that enable them to voluntarily participate in their own healthcare. Yipes is always free to choose whether or not he wants to participate, but we encourage him by offering incentives—pellets and cinnamon biscuits. Rewarding him with his favorite food for doing the correct behavior makes the experience a positive one for Yipes and helps build his trust in us. In the event he needed to undergo an exam, this practice enables him to do so voluntarily, making the whole process less stressful and lessening the need for anesthesia.

By the time Yipes turned 7 months old, Tara had built a strong bond with him. When he followed her cue and stepped on the scale for the first time, it was a very rewarding feeling. She was very proud that he did this behavior without hesitation, and she had earned his trust!  At his most recent weigh-in, Yipes tipped the scales at 431 pounds (196 kilograms). While he is making good gains, Yipes has about 320 more pounds to gain before he is the same size as his father, Rogan.

Although Yipes is becoming more independent, he seems to enjoy socializing with our young Przewalski’s horse colt, Zigmund, who lives in an adjacent pasture. When we need to mow the grass or do other routine maintenance, we will shift the colts away from each other for a short period. When they are reintroduced to their pastures, they become excited and run to greet one another like old friends—they vocalize, smell one another and touch noses.

Looking forward, we are excited to see what the future holds for our colt! In autumn, Hartmann’s mountain zebra breeding season will come to a close. Rogan will once again be separated from Yipes’ mother, Mackenzie, and her herd-mate, Xolani. Since male Hartmann’s mountain zebras do not play a role in raising their offspring, father and son have never shared a pasture. This could change, however, when Rogan becomes Yipes’ next-door neighbor and they have the opportunity to meet at a common fence line. If the “howdy” introductions go well, we may be able to start a Hartmann’s mountain zebra bachelor group!

This story was featured in the July 2021 issue of National Zoo News. Read previous keeper updates about Yipes from April 2021, February 2021, October 2020 and July 2020. Want animals in your inbox? Sign up for our e-newsletters.